Motor vehicles include fairly extensive associated electrical systems and such electrical systems are steadily becoming more sophisticated. The electrical systems of motor vehicles function to operate interior and exterior lighting systems, signals and auxiliary equipment such as windshield wipers, fans, radios, trip computers and the like. Recently, the trend has been to equip motor vehicles with a great number of servo motors for purposes of operating power sun roofs, adjustable mirrors, power windows, door and trunk locks and similar systems. All of these power consuming items are disposed in various locations on the motor vehicle and these items frequently display a wide range of power and/or voltage requirements.
As a result of the foregoing, the electrical systems of most motor vehicles are fairly complex. In addition to the extensive network of wiring, vehicular electrical systems include a great number of other components such as resistors, diodes, capacitors, transistors, fuses, voltage dividers and the like for purposes of providing electrical power having the proper polarity and voltage to the myriad of associated systems.
While it is possible to individually wire each the various components of motor vehicles, such a procedure is very expensive and tends to produce unreliable results. Consequently, manufacturers employ wiring harnesses. These are bundles of electrical wires which are usually color coded and which include necessary resistors, diodes and other circuit elements. The harnesses are prefabricated and installed during the course of the assembly of the vehicle. Because of the ever-growing concern for reliability and quality in the automotive business, manufacturers are now specifying that the resistors, diodes and other circuit elements of a wiring harness be environmentally sealed so as to prevent failure resultant from corrosion of contacts or environmental damage to the electrical component. Typically, such environmental sealing is accomplished by encapsulating the component and its associated wiring by means of heat-shrink tubing or similar material.
While a wiring harness thus fabricated is environmentally protected and ready to install in a motor vehicle, this process is not without its disadvantages. Many components such as diodes and transistors must be installed with proper regard to polarity. If, during the assembly of the harness, one such component is installed in a reversed orientation, the delivered power will not be proper and the energized system will be inoperative and/or damaged. Often times such errors are not discovered until the harness is installed and assembly of the vehicle completed. In such event, the improperly installed electrical component must be replaced, often at great expense and inconvenience. Such "hard wired" harnesses present further problems if a component fails during use since it will then be necessary to cut out the old component, splice in a new component, and reseal the junction. Of course, it is always possible that errors of polarity may be made during such a replacement.
It would clearly be desirable to have a wiring harness including environmentally sealed electrical components wherein inadvertent misinstallation of those components is prevented and replacement of defective components may be accurately and simply accomplished without compromising the environmental seal of the harness.
The present invention provides a package for electronic components having environmentally sealed, internal connections. The package may be readily removed and replaced from a wiring harness or the like. The present invention further includes specific configurations of plug-in electrical components matable with corresponding sockets in a predetermined polarity relationship.
Various configurations of plug-in electrical components have been known in the art for some time; however, such components have not heretofore included internal, environmentally sealed connections thereto, nor have they been incorporated into vehicular wiring harnesses. U.S. Pat. Nos. 2,634,352, 2,784,284, and 2,683,203 all disclose electrical resistors enclosed in a package having protruding, external electrical terminals. None of these patents disclose any configuration of electrical resistors which may be affixed to electrical circuitry in an environmentally sealed manner. Furthermore, none of these patents show any type of vehicular wiring harness. U.S. Pat. No. 3,566,003 discloses a diode configured into a plug-in, fuse-type package for connection to spring clip terminals. This patent does not teach the use of the diode in a vehicular wiring harness nor does it teach a diode package having environmentally sealed, internal connections.
As will be explained in greater detail hereinbelow, the present invention overcomes the problems of the prior art and provides electrical components which are environmentally sealed into an electrical circuit and which are readily replaced therefrom without compromising the seal. These and other advantages of the present invention will be readily apparent from the drawings, discussion, description and claims which follow.